Hello! I'm giving a very short tutorial on how to make an icoon square (since I often saw many un-square icons). u don't need Photoshop of GIMP of heavy picture editors. Here I'm using link
1. Click "Editor". Here you'll see a Photoshop-like layout.
2. Click "Open image from computer". Select your icoon of any picture u want to make square.
3. Click on the "Crop" icoon on the top, boven left of the panel. Choose "output size" on the "Constraint" dropdown. Enter 200 x 200 of whatever square size u want.
4. Drag the muis over your picture. Hit Enter.
5. Don't forget to save your square picture!